Oily cold water fish, such as salmon, trout, herring, and tuna are the source of dietary marine omega-3 fatty acids, with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) being the key marine derived omega-3 fatty acids. Omega-3 fatty acids have previously been shown to improve insulin sensitivity and glucose tolerance in normoglycemic men and in obese individuals. Omega-3 fatty acids have also been shown to improve insulin resistance in obese and non-obese patients with an inflammatory phenotype. Lipid, glucose, and insulin metabolism have been shown to improve in overweight hypertensive subjects through treatment with omega-3 fatty acids. Omega-3 fatty acids (EPA/DHA) have also been shown to decrease triglycerides and to reduce the risk for sudden death caused by cardiac arrhythmias in addition to improve mortality in patients at risk of a cardiovascular event. Omega-3 fatty acids have also been taken as dietary supplements part of therapy used to treat dyslipidemia, and anti-inflammatory properties. A higher intake of omega-3 fatty acids lower levels of circulating TNF-α and IL-6, two of the cytokines that are markedly increased during inflammation processes (Chapkin et al, Prostaglandins, Leukot Essent Fatty Acids 2009, 81, p. 187-191; Duda et al, Cardiovasc Res 2009, 84, p. 33-41). In addition, a higher intake of omega-3 fatty acids has also been shown to increase levels of the well-characterized anti-inflammatory cytokine IL-10 (Bradley et al, Obesity (Silver Spring) 2008, 16, p. 938-944). More recently, there is additional evidence that omega-3 fatty acids could play a significant role in oncology (Anderson et al, Lipids in Health and Disease 2009, 8, p. 33; Bougnoux et al, Progress in Lipid Research 2010, 49, p. 76-86; Erickson et al, Prostaglandins, Leukotrienes and Essential Fatty Acids 2010, 82, p. 237-241). In a study using the xenograft model in nude mice, treatment with omega-3 fatty acids, such as DHA and EPA, resulted in breast tumor regression. Here, treatment with DHA/EPA appeared to increase the level of PTEN protein and attenuate the PI 3 kinase and Akt kinase activity as well as the expression of the anti-apoptotic proteins Bcl-2 and Bcl-XL in the breast tumors (Ghosh-Choudhury, T. et al. Breast Cancer Res. Treat. 2009, 118 (1), 213-228). Additional evidence supporting the use of omega-3 fatty acids in oncology also appeared in a recent study by Lim et al. showing that DHA/EPA could inhibit hepatocellular carcinoma cell growth, presumably by blocking β-catenin and cyclooxygenase-2 (Lim, K. et al. Mol. Cancer Ther. 2009, 8 (11), 3046-3055).
Both DHA and EPA are characterized as long chain fatty acids (aliphatic portion between 12-22 carbons). Medium chain fatty acids are characterized as those having the aliphatic portion between 6-12 carbons. Lipoic acid is a medium chain fatty acid found naturally in the body. It plays many important roles such as free radical scavenger, chelator to heavy metals and signal transduction mediator in various inflammatory and metabolic pathways, including the NF-κB pathway (Shay, K. P. et al. Biochim. Biophys. Acta 2009, 1790, 1149-1160). Lipoic acid has been found to be useful in a number of chronic diseases that are associated with oxidative stress (for a review see Smith, A. R. et al Curr. Med. Chem. 2004, 11, p. 1135-46). Lipoic acid has now been evaluated in the clinic for the treatment of diabetes (Morcos, M. et al Diabetes Res. Clin. Pract. 2001, 52, p. 175-183) and diabetic neuropathy (Mijnhout, G. S. et al Neth. J. Med. 2010, 110, p. 158-162). Lipoic acid has also been found to be potentially useful in treating cardiovascular diseases (Ghibu, S. et al, J. Cardiovasc. Pharmacol. 2009, 54, p. 391-8), Alzheimer's disease (Maczurek, A. et al, Adv. Drug Deliv. Rev. 2008, 60, p. 1463-70) and multiple sclerosis (Yadav, V. Multiple Sclerosis 2005, 11, p. 159-65; Salinthone, S. et al, Endocr. Metab. Immune Disord. Drug Targets 2008, 8, p. 132-42).
Lenalidomide is an anti-cancer agent that has been approved by the FDA for the treatment of multiple myeloma in combination with dexamethasone. Lenalidomide has also been approved for use in patients with transfusion-dependent anemia due to Low or Intermediate-1-risk myelodysplastic syndromes (MDS) associated with a deletion 5q cytogenetic abnormality with or without additional cytogenetic abnormalities. Lenalidomide belongs to the Immunomodulatory imide Drugs (IMiDs) class of compounds and is essentially an analogue of thalidomide (Rajkumar et al, Blood 2005, 106, p. 4050-4053; Dredge et al, British J. Cancer 2002, 87, p. 1166-1172). In terms of mechanism of action, lenalidomide can act as immunomodulator agent because of its ability to inhibit IL-1β or TNF-α-induced activation of IκK, which in turn prevents dissociation of IκBα from NF-κB, precluding its nuclear translocation and induction of various genes that are responsible for metastasis, angiogenesis, cellular proliferation, inflammation and protection from apoptosis (Aragon-Ching et al, Recent Pat Anticancer Drug Discov. 2007, 2, p. 167-174). Pomalidomide is another derivative of lenalidomide that has also been shown to have interesting anti-cancer activity (Tefferi et al, J. Clin. Oncology 2009, 27, p. 4563-4569).
Because of the ability of lenalidomide and omega-3 fatty acid to act on the NF-κB axis, a synergistic activity would provide a great benefit in treating multiple myeloma, myelodysplastic syndromes (MDS) or other metabolic diseases.